Process for bleaching mercerized cotton and rayon yarns



Patented Feb. 1939 UNITED STATES hig PATENT OFFICE PROCESS FOR BLEACHING MERCEBIZED COTTON AND RAYON YARNS Edwin P. Sherman, High Point, N. 0., assignor to The Geo. E. Shaman Co mpany, Inc., Brooklyn, N. Y., a corporation of New York dclalms.

This invention relates to bleaching processes,

more particularly to a process for bleaching mer- V cerized cotton and rayon yarns, and is a division of my co-pending application for patent filed March 11, 1937, Serial Number 130,417.

Standard bleaching processes are relatively complicated and lengthy as, for example, the bleaching of cotton yarn, which involves substantially seven steps, as follows: boiling in caus 1o tic, as 2% caustic soda, 1% silicate and 1% sulphonated oil or the like, dropping the above bath and washing in hot water, dropping and running through hypochlorite solution, A to 2 TW, dropping and washing in warm water, dropping and souring in a hydrochloric acid or sulphuric acid solution or the like, dropping and washing in warm water, dropping and washing in water to which is added bluing.

. An object of this invention is to provide a go bleaching process which is much shorter than standard processes, and involves fewer steps.

Another object is to provide a bleaching process employing a compound containing oxygen and chlorine which process will inhibit the characteristic action of the chlorine upon the fibers without interfering with the action of the nascent oxygen.

Still another object is to provide an improved bleaching process which will be efilcient, even if the material to be bleached contains insoluble oils.

Another object is to provide a bleaching process which will leave the material free of oil stains, chafe marks and so-called niger beads.

Yet another object is to provide a bleaching process which is considerably less expensivfi than most standard bleaching processes for like material.

Other objects and advantages of the invention 40 will be apparent during the course of the following detailed description thereof.

After the material has undergone any prelimi- V narydesirabletreatment,suchasboilingoutin order to remove insoluble oils and the like, the a material is treated, preferably, to a bath containingwatentrisodiumphosphatesodaashand sodium stearate. For example, in the bleaching of mercerised cotton and rayon yarns of substantially 100 pound weight, the material may be u boiled out in a bath containing:-

200to250gallonswater 2% bywattrisodiumpbospha 4% bylmhsodaash 2%oywgtJodiumstearate (suchasgreenscap I6 145).

This treatment preferably continues for substantially five minutes, whereupon the bath may or may not be dropped and the material treated to a bath containing sodium hypochlorite and a bulier. The latter may be glues, saponified 5 and/or emulsified fats and oils, sulphonated oils, dextrines, glucose, sugar, fatty alcohols, alkali and alkaline salts.-

The sodium hypochlorite and bufferymay be mixed together in substantially the following pro- 10 by weight sodium ypochlorite 5% by weight buifer.

to 250 gallons water 2% by weight trisodium phosphate 2% by weight sodium stearate (such as green soap 145) 10% by weight sodium hypochlorite-buifer mixture.

It is preferred that, at the start, this bath be at a temperature of substantially 100 F. and a maintained at a temperature of between 100 F. and F. for about fifteen minutes, whereupon the bath is brought to a boil and boiling maintained for twenty minutes, after which the bath is dropped and the material rinsed in a bath containing about:

100 to 250 gallons water With the treatment described, the chlorine does not attack the material, being bleached, due to the proportions of buffers employed and the temperatures maintained.

Various changes may be made to the forms of the invention herein described, without departing from the spirit of the invention or the scope of the claims.

I claim:

1. A bleaching process for mercerized cotton and rayon yarns, which consists in boiling said u of the above numbered patent requiring correctionas follows:

material for substantially five minutes in a bath including trisodium phosphate, soda ash and sodium stearate, dropping said bath, subjecting said material to a bath, at between 100 F. and 118 51, consisting of trisodium phosphate, sodium stearate, sodium hypochlorite and a bufier, for substantially fifteen minutes, raising said temperature to the boiling point and boiling for twenty minutes, dropping said bath and rinsing said material;

v 2. A bleaching process for mercerized cotton and rayon yarns which consists in boiling said material for substantially five minutes in a bath including 2% by weight trisodium phosphate, 4% by weight soda ash and 2% by-weight sodium stearate, dropping said bath, subjecting said material to a bath, at between 100 Rand 110 F.,-

consisting of trisodium phosphate, sodium stearate, sodium hypochlorite and a bufier, for substantially fifteen minutes, raising said temperature to the boiling point and boiling for twenty minutes, dropping said bath and rinsing said material.

3. A bleaching process for mercerized cotton and rayon yarns which consists in boiling said 4. A bleaching process for mercerized cotton and rayon yarns, which consists in boiling said material for substantially five minutes in a bath including trisodium phosphate, soda ash and sodium stearate, dropping said bath, subjecting said material to a bath, at between 100 F. and 110 F., consisting of 2% by. weight trisodium phosphate, 2% by weight sodium stearate, and 10% by weight hypochlorite-bufier mixture for substantially fifteen minutes, raising said temperature to the boiling point and boiling for twenty minutes, dropping said bath and raising said material.

WIN P. SEER/IAN.

CERTIFICATE OF CORRECT-ION}, Patent or. 2,1l;8,8l 2.,

February 28 1959 v I I I EDWIN P. SHERMAN. It is hereby certified :that error. appears in the printed specification Page 2, second column, line 2h, claim L for the word "raising" read frinsing; and that the i said Letters Patent should be .-'r'ead with this correction therein that the same may conform to vthe record of the, ease in the Patent Offices Signed and sealed this 2nd day of May, Ann 19 9; I n

(Seal) H Henry Van Arsdale Acting Commissioner of Patents. 

